railway system vs railway

railway system and railway both are nouns.

Word	Noun	Adjective	Verb	Adverb
railway system	Yes	No	No	No
railway	Yes	No	No	No

As nouns, railway system and railway are synonyms defined as:

railway system and railway: line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight

Other synonyms of railway system include railroad, railroad line, railway line.

railway system (noun)	railway (noun)
line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight	line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight
	a line of track providing a runway for wheels